PHILADELPHIA (AP) — A medical examiner said he couldn’t fully analyze a woman’s death following a 2009 abortion until the clinic was raided months later.

Assistant Philadelphia Medical Examiner Gary Collins said he initially ruled it an accidental overdose death. But he said he changed the cause to homicide after getting clinic records and witness statements.

Dr. Kermit Gosnell is charged with third-degree murder in the alleged overdose death of Karnamaya Mongar, a 41-year-old refugee from Bhutan. Prosecutors said he let untrained staff administer controlled drugs.